Our Solar System Quiz
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5 questions, one answer each
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See all 5 questions
1. How many planets orbit the Sun in our Solar System?
- A. Six
- B. Seven
- C. Eight
- D. Nine
2. What is a nebula?
- A. A dying star
- B. A cloud of dust and gas that can form a star
- C. A type of artificial satellite
- D. The core of a planet
3. What force keeps planets and moons in their orbits?
- A. Magnetism
- B. Friction
- C. Gravity
- D. Electrostatic force
4. What balance is reached once fusion begins in a young star?
- A. Between magnetism and gravity
- B. Between gravitational collapse and the outward push of fusion energy
- C. Between temperature and pressure only
- D. Between mass and radius
5. (HT) In a stable circular orbit, why does an object's velocity keep changing even though its speed is constant?
- A. Because the gravitational force keeps changing size
- B. Because the direction of motion keeps changing due to the centripetal force
- C. Because friction slows it down periodically
- D. Because velocity always changes in space